Pain clinical trials at UCSF 4 in progress, 2 open to new patients

This study evaluates invasive deep brain stimulation (DBS) in the treatment of three types of chronic neuropathic pain, i) Post Stroke pain syndrome ii) Phantom Limb pain and iii) Spinal Cord Injury Pain. Participants will be implanted with recording / stimulation electrodes in pain-related circuits of the brain. Relief of pain symptoms with stimulation will be studied in both groups. It is hypothesized that neural signals will correlate with pain states and that DBS can disrupt these pain states in both groups, perhaps with differences in underlying neural mechanisms for pain relief.

Our primary objective is to assess whether inhaling vaporized cannabis ameliorates chronic pain in patients with sickle cell disease (SCD). As these patients will all be on chronic opioid analgesics, the investigators will also assess the possible synergistic affect between inhaled cannabis and opioids. The investigators will also assess the clinical safety of the concomitant use of cannabinoids and these opioids in patients with SCD by monitoring the short-term side effects associated with combined therapy. Finally, the investigators will evaluate the short-term effects of inhaled cannabis on markers of inflammation and disease progression in patients with SCD. Hypotheses are as follows: 1. Inhaled cannabis will significantly reduce chronic pain in patients with SCD. 2. Inhaled cannabis will significantly alter the short-term side effects experienced by patients who take opioids for SCD. 3. Inhaled cannabis will significantly alter markers of inflammation and disease progression in patients with SCD compared to placebo.